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Alfresco Content Services 5.2 Developer Guide Contents Contents Developer Guide........................................................................................3 Alfresco Content Services architecture............................................................................... 3 Alfresco Content Services architecture overview........................................................ 5 Access protocols........................................................................................................18 Repository concepts.................................................................................................. 19 Mini glossary..............................................................................................................24 Alfresco SDK 2.2.0............................................................................................................ 28 What's new?.............................................................................................................. 28 Introduction to the Alfresco SDK............................................................................... 30 Getting Started with the Alfresco SDK...................................................................... 35 Maven Archetypes - Command Reference............................................................... 56 Rapid Application Development (RAD)..................................................................... 65 Advanced Topics....................................................................................................... 95 Upgrading.................................................................................................................125 Using the REST API Explorer................................................................................. 170 Using MySQL...........................................................................................................171 Developer Guide 2 Developer Guide Developer Guide The Developer Guide includes extensive guidance and reference materials to aid the developer in creating applications and extensions for Alfresco. This Developer Guide PDF does not include the full developer documentation and API references. To access the complete set of documentation, see the online Alfresco documentation. There are a number of approaches to developing for Alfresco depending on what you want to do. For example, if you are writing a client application, perhaps in Ruby or Python to connect to Alfresco either on-premise, or Alfresco in the Cloud, then you would most likely use the Alfresco REST API. If on the other hand you wanted to write a server-side extension in Java, you would use the Public Java API, or perhaps write a web script using Java, JavaScript and FreeMarker. Generally if you are creating extensions to Alfresco you would use the Alfresco SDK. This allows you to work in your IDE of choice, using technologies you already know, such as Java and Maven. This Developer guide attempts to lay out the various options available to you, so you can use the right approach, depending on what you want to achieve. Alfresco Content Services architecture This gives a view of the architecture of Alfresco Content Services from the developer's perspective. At its core is a repository that provides a store for content, and a wide range of services that can be used by content applications to manipulate the content. The following diagram illustrates the idea that can be thought of as consisting of three main components, Platform, User Interface (UI), and Search. These components are implemented as separate web applications: The main component is called the Platform and is implemented in the alfresco.war web application. It provides the repository where content is stored plus all the associated content services. Alfresco Share provides a web client interface (that is a User Interface, UI) for the repository and is implemented as the share.war web application. Share makes it easy for users Developer Guide 3 Developer Guide to manage their sites, documents, users and so on. The search functionality is implemented on top of Apache Solr 4 and provides the indexing of all content, which enables powerful search functionality. Besides the web clients accessing the Repository via Share there are also mobile clients that will access the content via REST APIs provided by the platform. If we dive deeper into the platform (packaged in alfresco.war) we will see that it also supports workflow in the form of the embedded Activiti Workflow Engine. The platform is usually also integrated with a Directory Server (LDAP) to be able to sync users and groups with Alfresco Content Services. And most installations also integrates with an SMTP server so the Platform can send emails, such as site invitations. For more information about the internals of the Platform, and specifically the content repository, see the concepts section. Besides Share there are also many other clients that can connect to the repository, including any CMIS-compatible client, and via the Microsoft SharePoint protocol any SharePoint client. Enterprise to Cloud Sync can synchronize content between an on-premise installation of and in the Cloud, under user control. The Platform also contains numerous APIs, Services, and Protocols. The following diagram illustrates this extended architecture: Note that content metadata is stored in a relational database system such as PostgreSQL, MySQL, Oracle, and so on. The content itself is stored on the file system (or other storage system such as Amazon S3). Alfresco provides a number of extension points to allow you to customize it. These extensions points have various formats, but include: • Platform extension points and detailed architecture • Share extension points and detailed architecture • Share integration points and detailed architecture • APIs • Protocols • Services The links in the list above provide further information on each of these topics. Developer Guide 4 Developer Guide Alfresco Content Services architecture overview At the core of the Alfresco Content Services system is a repository supported by a server that persists content, metadata, associations, and full text indexes. Programming interfaces support multiple languages and protocols upon which developers can create custom applications and solutions. Out-of-the-box applications provide standard solutions such as document management and records management. As a Java application, the system runs on virtually any system that can run Java Enterprise Edition. At the core is the Spring platform, providing the ability to modularize functionality, such as versioning, security, and rules. Alfresco Content Services uses scripting to simplify adding new functionality and developing new programming interfaces. This portion of the architecture is known as web scripts and can be used for both data and presentation services. The lightweight architecture is easy to download, install, and deploy. There are many ways to deploy, however most deployments follow a general pattern. Ultimately, Alfresco Content Services is used to implement ECM solutions, such as document management and records management. There can also be elements of collaboration and search across these solutions. The solutions are typically split between clients and server, where clients offer users a user interface to the solution and the server provides content management services and storage. Solutions commonly offer multiple clients against a shared server, where each client is tailored for the environment in which it is used. Clients Alfresco Content Services offers a web-based client called Alfresco Share, built entirely with the web script technology. Share provides content management capabilities with simple user interfaces, tools to search and browse the repository, content such as thumbnails and associated metadata, previews, and a set of collaboration tools such as wikis and discussions. Share is organized as a set of sites that can be used as a meeting place for collaboration. It's a web-based application that can be run on a different server to the server that runs the repository, providing opportunities to increase scale and performance. Share can be deployed to its own tier separate from the content application server. It focuses on the collaboration aspects of content management and streamlining the user experience. It's implemented using Surf and can be customized without JSF knowledge. Clients also exist for portals (by using JSR-168 portlets), mobile platforms, Microsoft Office, and the desktop. In addition, using the folder drive of the operating system, users can share documents through a network drive. Using JLAN technology, Alfresco can look and act just like a folder drive. JLAN is the only Java server-side implementation of the CIFS protocol, letting users interact with Alfresco Content Services as they do any other normal file drive except the content is now stored and managed in the content application server. Server The content application server comprises a content repository and value-added services for building solutions. The content application server provides the following categories of services built upon the content repository: • Content services (transformation, tagging, metadata extraction) • Control services (workflow, records management, change sets) • Collaboration services (social graph, activities, wiki) Clients communicate with the content application server and its services through numerous supported protocols. HTTP
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